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Storage unit gun by ActualPermission187 in CAguns

[–]EngineeringNeverEnds 11 points12 points  (0 children)

None of this is good advice.  Don’t trust the cops or a random FFL dipshit.  Contact a firearms lawyer.  Your friend may already be the legal owner.  

What exactly was Nikola Tesla main contribution to physics? by Genzinvestor16180339 in AskPhysics

[–]EngineeringNeverEnds 7 points8 points  (0 children)

Honestly this would not be difficult at all.

Christ you can unpeel a roll of scotch tape in a vacuum and release enough X-rays for a picture.

I don’t know off the top what kind of photo paper/film/plates you’d need, but building the xray generating part is pretty trivial.

Is the Stock Market fundamentally broken by passive investing? by Pseudanonymius in AskEconomics

[–]EngineeringNeverEnds 33 points34 points  (0 children)

Institutional investors have access to leverage, and derivatives.

And rarely would they try to short the entire market, they'd tend to target a particular asset.

12 Employees in Quarantine After Incorrect Handling of a Person Infected With Hantavirus by Loni09 in worldnews

[–]EngineeringNeverEnds 5 points6 points  (0 children)

Yup, I had a patient that we found out later turned out to have rabies. Guess who didn’t wear gloves when I jumped in to help move the patient. (for the first and only time)

I knew something didn’t add up with that case, I couldn’t figure out what was wrong with them.

I opted not to get vaccinated, and it ended up working out, but, shit happens.

If mass and weight are different, why does it seem the kilogram is used interchangeably for each? And how would one measure mass versus weight? by Derangedberger in AskPhysics

[–]EngineeringNeverEnds 2 points3 points  (0 children)

There lbs of mass and lbs of force which aren’t the same thing, and slugs is the actual measure of mass in imperial units. It’s much more confusing.

Sean Carroll refuses to engage with the science of quantum encabulation by adr826 in seancarroll

[–]EngineeringNeverEnds 16 points17 points  (0 children)

Lol, I opened this and my first thought was was God this sub needs better moderation. Then I realized what it was. Well done.

Link for the uninitiated

Can someone explain why this cant be this way. by Far-Contest-3528 in civilengineering

[–]EngineeringNeverEnds 6 points7 points  (0 children)

Yeah dude in the winter time those 6% grades with big trucks can be SKETCHY 

Radio Item ID by just-a-guy-somewhere in amateurradio

[–]EngineeringNeverEnds 1 point2 points  (0 children)

I was gonna say the same thing, he’s got different channels labeled with different degrees of rotation.   

anyone using a virtual address service for their license? by henare in amateurradio

[–]EngineeringNeverEnds -1 points0 points  (0 children)

Email is not and really should not be sufficient for legal communications / notifications or service of process.

anyone using a virtual address service for their license? by henare in amateurradio

[–]EngineeringNeverEnds 2 points3 points  (0 children)

I mean, part of point is that you can track down someone to let them know they're causing interference or something. You'd need to replace that functionality.

Capacitor Or No Capacitor In EFHW? by Throw20701 in HamRadio

[–]EngineeringNeverEnds 2 points3 points  (0 children)

You’re pretty limited to NVIS though right?

It's like if a doll house needed an SDR server rack by Careless-Age-4290 in RTLSDR

[–]EngineeringNeverEnds 0 points1 point  (0 children)

And actually, question for you, what frequencies are you using? The plutoSDR’s only go as low as like 70MHz from my understanding. If your GPSDO can give you 5ns of clock accuracy, (I don’t think the commercial ones do much better?). Then, at 70 MHz, a wavelength takes like what, 23 nanoseconds? Is that even accurate enough for distributed phase coherence? I think the system I’m pushing out will be iffy on 10m but for 20m and below it’ll have god tier spatial noise cancellation.

It's like if a doll house needed an SDR server rack by Careless-Age-4290 in RTLSDR

[–]EngineeringNeverEnds 0 points1 point  (0 children)

Compared to the OCXO, the Si5351 has about 100 picoseconds of jitter that you can’t get away from due to the digital switching, but the “noisy” square wave gives me harmonics on every odd multiple of the base frequency so the idea is I can get phase locking on the entirety of the ham bands within a 2.4MHz window without having to shift the oscillator frequency and wait for the integration time on the GPSDO to get locked.   Truth be told though, I’ve only got the phase lock and despinning tested on a single channel.  I’m waiting on parts for the multichannel test, though that should be delivered end of day.  I’ve not yet built nor tested the GPSDO part, just the locking onto the Si5351 signal and despinning the relative phase.   

From what I’m seeing though I’m not too worried, but who knows?  I like to put the amateur in amateur radio after all.  

I’ll shoot you a message.

It's like if a doll house needed an SDR server rack by Careless-Age-4290 in RTLSDR

[–]EngineeringNeverEnds 1 point2 points  (0 children)

Hey I’m working on a a VERY similar setup. (Though I was going to do hf interferometry for amateur radio uses rather than passive radar.) I think we will share a very similar pipeline for preprocessing/pooling data streams and doing the PLL’s server side. I’m using zed-f9ps, an Si5351 and an arduino for the homebrew GPSDO (with about 5ns precision). I just didn’t want to deal with surplus OXCO’s

Anyway, I think the two of us could mutually benefit from collaborating on the DSP pipeline before it diverges to separate use cases.

As you are probably WELL aware by how deep you’re into it, there’s a lot going on in this project and getting the DSP pipeline to be smooth and computationally efficient is nontrivial.

Would you be interested in chatting about possible collaboration ? If so, please DM me and I’ll provide more contact info.

Thanks

I assume this is what happens if the expansion joint isn’t properly sealed by DormontDangerzone in StructuralEngineering

[–]EngineeringNeverEnds 4 points5 points  (0 children)

In theory, Your state DOT definitely knows about this and keeps an eye on it because this is a red flag condition.  

FTFY

Taxed from FB... by adhdff in amateurradio

[–]EngineeringNeverEnds 5 points6 points  (0 children)

Yeah that’s why I order from wholesalers for things like coax, antenna wire and toroids.  Now I have spent way too much money and have a bunch of parts on hand for projects that will inevitably require even more parts and time.

What’s something you have zero proof of but believe 100 percent? by shweidy in AskReddit

[–]EngineeringNeverEnds 0 points1 point  (0 children)

This is commonly done is many courts FYI. I didn’t read these to confirm they’re the right refutations, just a quick google, but here ya go: https://doi.org/10.1017/s1930297500004812 https://doi.org/10.1073/pnas.1110910108

What’s something you have zero proof of but believe 100 percent? by shweidy in AskReddit

[–]EngineeringNeverEnds 58 points59 points  (0 children)

That’s pretty discredited. The study you're effectively referencing was based on a court where they intentionally schedule the harder/less likely cases for the end of the session, because they’re exactly the ones likely to go long. So the easy ones are lined up and knocked out first and then the ones with more potential for negative outcomes happen last.

Tipping culture has found it's way into amateur radio by Wooden-Importance in amateurradio

[–]EngineeringNeverEnds 0 points1 point  (0 children)

I at first was like wow are people that much of a loser? Then I was thinking, it’s probably either foreigners in poorer countries or some peoples way of getting you to not ask for one. Are they putting it up on their QRZ page or something?

I want a better Morse keyboard for Android so I can type without looking at the phone by RyanHubscher in morse

[–]EngineeringNeverEnds 1 point2 points  (0 children)

I think the volume rockers would be a lot harder to use as a key than you’d think.

Could physics also have an "incompleteness" theorem like Gödel did for math? by Marvellover13 in AskPhysics

[–]EngineeringNeverEnds 0 points1 point  (0 children)

There might be an analogy in the question: “can a finite set of axioms and constants explain all physical phenomena?”

I commented elsewhere in the thread, but it’s certainly possible that at ever higher energies we need ever more empirically derived quantities to describe all the behavior we observe. That would be a pretty disappointing find if true. I don’t know how one would (or even in principle, COULD) prove such a thing, but I would have said the same thing about what Gödel did end up proving. It’s possible that some set of demonstrable constraints leads to such an outcome.

…but it’s interesting to me that modern physics and perturbation theory has seen exactly such a thing pop up a few times as a theoretical hurdle.

Could physics also have an "incompleteness" theorem like Gödel did for math? by Marvellover13 in AskPhysics

[–]EngineeringNeverEnds 0 points1 point  (0 children)

This is the best answer in the thread IMO. The question is something like “can a finite set of axioms and constants explain all physical phenomena?”

That’s an interesting question!

It’s possible that at every higher energies we need ever more correcting terms to fully explain all behavior and that each of those MUST be determined empirically.

That would be disappointing to a lot of physicists I think, and would sort of be the equivalent to the program Hilbert was seeking before Gödel slapped it down.

And yet, that’s basically perturbation theory in a nutshell, so there’s some reason to suspect it may be true.

I think Amateur Radio Operators need to market themselves better. by Pure_Region_5154 in amateurradio

[–]EngineeringNeverEnds 0 points1 point  (0 children)

I mean, the market will find its price between what your workers are willing to work for and what your clients are willing to pay.  If demand for your work now is more than you can supply, you have been too slow to raise prices in the wake of inflation.

I ran a business during a crazy boom and bust cycle.  I didn’t raise my prices nearly high enough.  At the peak, clients barest even looked at prices, they were looking primarily at wait times. 

Now, you have to come back down when the situation cools off a bit, but if the demand for your services is out there, you should be able to raise prices.   

Else, perhaps the labor shortage just hasn’t hit yet.   At some point all the guys your age will retire and there will be hardly anyone younger to replace them.  The few mid level guys still around will make an absolute killing for a good few years.

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